A large portion of products sold in commerce in the United States is transported by truck. Consequently, theft from delivery vans, trucks and storage facilities is a serious concern. Locks that are generally provided by the manufacturers of delivery trucks and trailers used on semi-trailers are often inadequate to resist the assault of a determined thief who intends to break into the van, truck or trailer to steal the products therein. Thus, it is common in the industry to use high strength hasps and locks to provide additional protection against breaking and entering and theft from trucks and storage facilities.
An exemplary high strength hasp for use with a puck type lock is depicted in FIG. 1. A puck type lock is a non-conventional type of padlock originally invented for use in protecting cabinets of vending machines. A puck lock includes a flat generally cylindrical housing that defines a slot shaped trough or channel extending into one of the flat faces of the housing. A slot or channel is adapted to accept the staple portions of a hasp within. The puck lock further includes a bolt which can slide across the trough or channel and through the openings in the staple portions in the hasp to secure the staples together. The obvious advantage of a puck lock is that it does not have an exposed U-shaped shackle as does a conventional padlock. The internal bolt that passes through the staples is entirely enclosed in a heavy protective housing. Therefore, a puck lock provides greater protection from efforts to cut the shackle to gain access to the contents of the protected structure than does a conventional padlock.
Determined thieves can still attack portals secured with puck locks, however. If the puck lock is placed onto a conventional hasp the hasp can sometimes be broken by prying the hasp from the door, hammer blows or gripping the puck lock with a large pipe wrench or other tool and twisting the puck lock to separate the staples from the hasp. Thus, special high strength hasps with protective features have been developed.
Referring to FIG. 1, a prior art high strength hasp includes two plates that can be secured to two panels of a door or a door and doorjamb. Each plate supports a hasp staple, the two of which are opposed so that, when the door is closed, openings in the staples are aligned so that the bolt of a puck type lock or the shackle of a padlock may pass through them to lock together the two halves of the hasp. The high strength hasp also includes a protective partial ring that is sized and shaped to at least partially surround the periphery of a puck type lock to provide additional protection against the lock being forced open by thieves. The partial ring shaped protector is sized to fit closely about the perimeter of a puck type lock. The ring must fit closely to provide good protection. Otherwise, prying tools can be inserted into the space between the ring and the puck lock to pry in an attempt to break the hasp.
Since it is necessary for the ring shaped protector to fit snugly around the puck lock, problems arise. A puck lock can weigh several pounds. It becomes difficult and awkward for an operator firmly grasp the relatively heavy puck lock to insert the it inside the protective ring without pinching fingers. Further, if the puck-shaped lock is dropped there is a significant risk of injury to the operator's feet or of damage to merchandise that the lock may drop onto because of the substantial mass of the puck lock.
Further still, a loose puck lock is readily stolen or lost. When the delivery van or truck doors are opened the puck-shaped lock must be set aside somewhere and it is easy for the operator to forget to return the puck-shaped lock to the closed doors and leave it behind at a delivery location. Lastly, sometimes the operator will simply forget to put the puck-shaped lock on to lock the doors when departing. Often the puck lock is placed on the bumper or tailgate of the van and forgotten. The puck lock then falls from the truck en route and is lost.